Why didn't I come up with this simple upgrade to the QMX+?

This is an upgrade to the QMX+ which is so simple that I keep saying to myself: why did it take so long for someone to come up with it?

It consists only of doubling the PA transistors. The original 4 BS170s are paralleled with 4 more as shown in my implementation in the image. Very simple!

It is, as far as I understand, the brain child of Roelof PA0RDT and is described in detail on the QRPLabs website. I essentially followed those guidelines, and got more or less the same results as reported there.

There are several advantages:

• Approximately doubled output power
• More robustness to applied voltage. My QMX, wired for 9 Volts, now runs fine on 11 and more Volts, with a current limited power supply (approx. 2 Amps). 

I have had many FT8 contacts with it - where the transmitter is on continuously for 13 seconds - and have not had any problems. The only downside that I have heard of is slightly reduced power on 6 m due to the effect of the increased gate capacitance with two instead of one transistor.

Radio amateur endorses my latest book

Last fall I published the book "The Imagined Conflict". One of the endorsers is John Lennox, with whom I share the radio amateur hobby. His callsign during his most active days was GI3NSP,  at present it is G3NSP. 

Here's his commendation from the book's webpage:

“Holm’s book is an excellent addition to the literature on science and religion. With a delightful Scandinavian flavor, and with the keen insight of a practicing research physicist, Holm takes a balanced, three-pronged approach to the topic—historical, scientific, and philosophical. This book is a model of fair enquiry, and I thoroughly recommend it to anyone interested in understanding how science and the Christian faith can both coexist and thrive in fruitful dialogue.”

—John C Lennox, Emeritus Professor of Mathematics, University of Oxford

Thanks, John!

 

Do deer like antenna wires?

Our garden is frequently visited by roe deer. They like to trek along the little brook that runs at the edge of the garden. Usually that has few consequences.

But this weekend as I was about to contact stations during the CQ160CW contest, I noticed that nobody could hear me. I heard many stations, but nobody seemed to hear my signal.

The Imagined Conflict

I have a new independent blog named after my book "The imagined conflict". The book was published in November 2025 and is a revised translation of a book first published in Norwegian in 2021 and in a second printing in 2022. 

The new blog may be reached by clicking here.

Science with Overtones

Science with Overtones:
21 Natural Scientists and Their Belief in God.

Scientists with a belief in God have played a central role in the development of science for more than four hundred years. Some might think that belief in a creator God and the practice of science must have been a source of conflict, but the stories of the scientists tell a completely different story. They had a divine perspective on science, and it made their work better, not worse. Be inspired by 21 of the world's most important scientists!

The book has two authors. First, Professor Sverre Holm presents the scientist's life's work and beliefs, then Sven Aasmundtveit reflects on what this can mean for us today.

The book is in Norwegian and in sale from October 30.

My Ruyage UV58Plus changed into a completely new radio

New look (M70CM 3.2/P2.0)

I bought the Ruyage UV58Plus (also called Radtel 890) in August 2023. I liked its display as it would show both the frequency and the name of the station at the same time, and many Chinese handheld transceivers don't do that.

On the other hand, its scanning function wasn't very good, so I was a little disappointed. It sensitivity was also poorer than that of my Baofeng UV-5RE. But at a cost of 34 Euros + VAT, it was OK.

But that was before I found out that its firmware could be updated. I had originally V1.33, 2023-02-10. The images below show it with V1.35 2023-10-20.

The surprising faith of scientists

Equations representing many of the scientists in the book

"The surprising faith of scientists" is the tentative title of a book manuscript just submitted. 

The book stems from a discovery I made some time after I had completed my university studies where I had studied theories named after the likes of Pascal, Ampere, Faraday, Maxwell, and Kelvin. The surprising thing was that all of these were devout Christians. It would turn out that there were many more of them.

The magic of adaptive filters in amateur radio

Examples of a speech signal (top),
a sinusoidal, and noise (bottom)

Radio amateurs have been using adaptive noise reduction and adaptive notch filters for decades. They came with the advent of audio digital signal processing. 

Few however, understand how different they are from ordinary frequency selective filters and for many they appear to do something magic, very different from ordinary filters.